[lxgr]

My guess would be: QWERTZ touch typing was not a common skill in most pilots at the time these were introduced, and an ABC layout is slightly more ergonomical than QWERTZ for users not familiar with either.

Now that's changed, but changing the keyboard now would ruin older pilots' muscle memory.

[rounce]

You’re likely not touch typing with two hands anyway because it’s often down on the centre console. Besides they’re primarily used for entering flight info into the FMS, not for long form messages.